Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.db.common / src / org / simantics / db / common / request / TransientUnaryRead.java

diff --git a/bundles/org.simantics.db.common/src/org/simantics/db/common/request/TransientUnaryRead.java b/bundles/org.simantics.db.common/src/org/simantics/db/common/request/TransientUnaryRead.java
new file mode 100644 (file)
index 0000000..bd9cb06
--- /dev/null
+++ b/bundles/org.simantics.db.common/src/org/simantics/db/common/request/TransientUnaryRead.java
@@ -0,0 +1,48 @@
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ *     VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.db.common.request;\r
+\r
+import org.simantics.db.ReadGraph;\r
+import org.simantics.db.exception.DatabaseException;\r
+import org.simantics.db.service.QueryControl;\r
+\r
+abstract public class TransientUnaryRead<P, R> extends BinaryRead<Object,P,R> {\r
+\r
+       protected static final Object WITH_PARENT = new Object();\r
+       \r
+       public TransientUnaryRead(ReadGraph graph, P parameter) throws DatabaseException {\r
+               this(graph, graph.getService(QueryControl.class), parameter);\r
+       }\r
+       \r
+       public TransientUnaryRead(ReadGraph graph, QueryControl qc, P parameter) throws DatabaseException {\r
+               super(resolveFirstParameter(graph, qc), parameter);\r
+       }\r
+\r
+       final private static Object resolveFirstParameter(ReadGraph graph, QueryControl qc) throws DatabaseException {\r
+               if(qc.hasParentRequest(graph)) return WITH_PARENT;\r
+               else return graph.getModificationCounter();\r
+       }\r
+\r
+       @Override\r
+       final public R perform(ReadGraph _graph) throws DatabaseException {\r
+               if(parameter == WITH_PARENT) {\r
+                       return perform(_graph, parameter2);\r
+               } else {\r
+                       QueryControl qc = _graph.getService(QueryControl.class);\r
+                       ReadGraph graph = qc.getIndependentGraph(_graph);\r
+                       return perform(graph, parameter2);\r
+               }\r
+       }\r
+\r
+       abstract public R perform(ReadGraph graph, P parameter) throws DatabaseException;\r
+    \r
+}\r